Search Publications
Determination of physical properties of a planetary surface by measuring the deceleration of a probe upon impact: Application to Titan
Lorenz, Ralph D.; McKay, Christopher P.; Seiff, Alvin +3 more
We report scale model laboratory experiments showing how an impact accelerometer on a planetary probe (based on the Huygens probe Phase A configuration) can provide significant information on the mechanical characteristics of the surface. In particular, solid and liquid surfaces can be discriminated. The density of liquids can in principle be dete…
Detection of thermal X-ray emission in the halo of the plerionic supernova remnant G21.5-0.9
Bocchino, F.
The detection of a soft thermal X-ray component in the spectrum of a bright knot in the halo of the plerion G21.5-0.9 is reported. Using a collisional ionization equilibrium model for an hot optically thin plasma, a temperature of kT 0.12-0.24 keV, a mass of 0.3-1.0 M⊙ and a density of 1.6-6 cm -3 is derived. The spectral ana…
Physical properties as indicators of liquid compositions: Derivation of the composition for Titan's surface liquids from the Huygens SSP measurements
Lorenz, R. D.; Hagermann, A.; Leese, M. R. +5 more
We present a method for inferring the relative molar abundance of constituents of a liquid mixture, in this case methane, ethane, nitrogen and argon, from a measurement of a set of physical properties of the mixture. This problem is of interest in the context of the Huygens Surface Science Package, SSP, equipped to measure several physical propert…
Effect of the latitudinal distribution of temperature at the coronal base on the interplanetary magnetic field configuration and the solar wind flow
Li, Xing; Habbal, Shadia Rifai; Li, Bo +1 more
Using a two-dimensional MHD model of the corona and solar wind, we investigate the role of the temperature distribution with latitude at the coronal base on the global magnetic field configuration and solar wind properties at 1 AU. The latitudinal distribution of temperature is aimed at modeling the transition in electron temperature at the Sun fr…
A Chinese-European Multiscale Mission: The Double Star Program
Cao, J. B.; Liu, Z. X.; Escoubet, P.
Stream-Field Interactions in the Magnetic Accretor AO Piscium
Hellier, Coel; van Zyl, Liza
UV spectra of the magnetic accretor AO Psc show absorption features for half the binary orbit. The absorption is unlike the wind-formed features often seen in similar stars. Instead, we attribute it to a fraction of the stream that overflows the impact with the accretion disk. Rapid velocity variations can be explained by changes in the trajectory…
New cluster candidates in the extended XMM Lockman Hole field
Finoguenov, A.; Streblyanska, A.; Hasinger, G. +2 more
We describe the results of a search for diffuse sources in the 0.4 deg 2 area of the XMM-Newton 770 ks survey of the Lockman Hole. An abundant population of sources is revealed, which is likely to stem from low-mass galaxy clusters at redshift near 1. We present the optical images in the K' and R-bands for our candidates, suggesting a c…
The Observational Evidence on the Loop Loop Interaction in a Flare CME Event on April 15, 1998
Huang, G. L.; Tang, Y. H.; Wu, G. P. +1 more
The evolution of the soft X-ray and EUV coronal loops related to the April 15, 1998 solar flare-CME event is studied with multiwavelength observations including hard X-rays (BATSE), microwaves (NoRP, CNAO) and magnetograms (SOHO/MDI), as well as images from Yohkoh/SXT and SOHO/EIT at 195 Å. It is shown that: (1) two soft X-ray and EUV loops rose, …
Observations of a Unique Cusp Signature at Low and Mid Altitudes
Winningham, J. D.; Balogh, A.; Fazakerley, A. N. +7 more
Observations of a unique cusp feature at low and mid altitudes are reported. This feature has a consistent double-peaked or “V”-shaped structure at the equatorward edge of high-latitude particle precipitation flux, and is predominantly present for high IMF By conditions. The observations are consistent with the Crooker (‘A split separat…
Planetary science: Are there active glaciers on Mars? (Reply)
Jaumann, R.; Head, J. W.; Neukum, G. +11 more
Gillespie et al. concur with our interpretation that certain lobate equatorial and mid-latitude features on Mars are due to debris-covered glaciers formed largely during past periods of increased spin-axis obliquity, when climate regimes favoured snow and ice accumulation and glacial flow. They suggest that the `hourglass' deposit, dated at more t…